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メタラートによる再配置によって可能になった触媒結合クロスカップリング
Liang Zhang1, Gabriel J Lovinger1, Emma K Edelstein1
1Department of Chemistry, Boston College, Chestnut Hill, MA 02467, USA.
Science (New York, N.Y.)
|January 2, 2016
まとめ
研究者は従来の伝達反応を回避する 新しいパラジウム触媒反応を開発しました この新しい金属酸塩の再配列は,オルガノリチウムとオルガノボロナートをオルガノトリフラートと効率的に結合させ,キラルなオルガノボロンエステルを作ります.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- 移行金属の触媒は現代の有機合成に不可欠です
- 多くの触媒サイクルには,スズキ-ミヤウラ結合のような有機金属転移のステップが含まれています.
- 合成能力を拡張するための代替反応経路が必要である.
研究 の 目的:
- 金属触媒反応における有機金属伝送ステップに新しい代替案を導入する.
- パラジアム誘発の金属酸塩の再配置メカニズムを 示すために
- キラルオルガノボロンエステルを合成するための新しいクロスカップリング反応を開発する.
主な方法:
- オーガノボロナートとオーガノリチウム反応剤からビニルボロンエステルアート複合体を製造する.
- パラジウム触媒を用いて1,2回転移を誘導する.
- エナチオセレクティブ合成のためのキラルパラジウム触媒を使用する.
主要な成果:
- ビニルボロンエステルエイト複合体は,パラジアム誘発の金属酸塩再配置を受けます.
- この再配列は,アルキルまたはアリル群の1,2のボロンからビニルα-炭素への移行を伴う.
- このプロセスはC-Pd σ結合を形成し,新しいクロスカップリング反応を可能にします.
- チラルのオルガノボロンエステルは,3つの単純な起始材料から高エナチオ選択性で合成された.
結論:
- 新しい基本的な反応,パラジアム誘発の金属酸塩再配置が確立されています.
- この反応は,クロスカップリングにおける伝統的な伝送に代わるものです.
- 開発された方法は,エナチオメリックに富んだオルガノボロンエステルへの効率的なアクセスを提供します.
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